The aims of this research are the synthesis of novel imidazo [4,5-e]-1,3-diazepines, and a preliminary investigation of their interaction with some enzymes of purine metabolism. The compounds to be prepared are structurally related to the naturally occurring 6-oxopurines by the formal insertion of a carbon atom into the six-membered ring. Synthesis of these previously unreported heterocyclic compounds will be achieved by ring closure of a suitably substituted imidazole. The chemistry of these novel compounds will be explored, as will their interaction with the enzymes xanthine oxidase, guanase, and purine nucleoside phosphorylase. By these means the potential of imidazodiazepines to serve as purine analogs will be determined.